Cartridge case



Jan. 16, 1968 H. STADLER ETAL 3,363,562

CARTRIDGE CASE 2 Sheets-Sheet I Filed oct. 29, 1964 FIG. 5

FIG. 3

FIG. I

FIG. 4

FIG. 2

INVENTORS. HANS STADLER HEINZ GAWLICK RUDOLF STAHLMANN HANS UMBACH @M70 ATTORNEYS Jan. 16, 1968 H. sTADLl-:R ETAL 3,363,552

CARTRIDGE CASE Filed Oct. 29, 1964 2 Sheets-Sheet 2 INVENTOR. HANS STADLER HEINZ GAWLICK RUDOLF STAHLMANN HANS UMBACH United States Patent 4 Claims. (ci. 1oz-4s) The present invention relates to cartridges cases, and more particularly to plastic projectile or shell cases for trench mortars.

The case of a projectile or shell cartridge of trench mortars ordinarily consists of a cardboard case with a cardboard plug or stopper and a bottom cap of metal.

Neither during the loading nor during the ring must the case become detached from and fall or drop out of the projectile or shell; if the case were to separate from the mortar shell or grenade and were to remain in the barrel, the ring possibility of the next following shell would be jeopardized.

To hold the projectile or shell cartridge to be fired in the shell or projectile by a bottom piece is yas such possible but is expensive and complicated. Consequently,

one has provided the cardboard case with an annular bead Whose diameter is larger than that of the bore of the cartridge chamber so that the case has to be pressed into the cartridge chamber and is held fast thereat -by a friction seat.

The new development of the present invention consists in replacing the prior art cardboard case of the red shell cartridge by a plastic cartridge case. The problem resulting from such substitution is to so construct the plastic cartridge case that it can also -be inserted with frictional engagement into the cartridge chamber. One could transfer the known arrangement of an yannular bead used heretofore with the cardboard case to the plastic case, but would then have to manufacture the same in the form of two separate shells which are subsequently connected by welding or gluing, thereby involving a manufacture that is both complicated and expensive.

It becomes possible by the present invention to so construct a plastic case, made in one piece, for tired shell cartridges of trench mortars that it produces the necessary frictional engagement, and more particularly by the fact that ribs are formed into the plastic case along the circumference thereof whose external contact circle, measured in the circumferential direction, is larger than that of the cartridge chamber. The plastic materials of known conventional type suitable for use with such cases are normally more or less yielding. If the cartridge is inserted, then the ribs deform easily and produce a good frictional contact that prevents with certainty a falling or dropping out on the part of the cartridge out of the shell or grenade.

Such ribs arranged at the circumference can be injection molded in one operation and in one piece with the cartridge case so that no additional operating steps as gluing or welding are necessary.

The ribs may extend either over the entire length or o'ver a part of the case in the longitudinal direction thereof. However, the ribs may also be of circular shape, approximately similar to the sealing ribs in bottle closure devices of plastic material, or in the form of a cone open in the direction toward the cartridge bottom. If continuous ribs extending over the entire length prove themselves as excessively rigid, they can also be subdivided into individual partial pieces.

Accordingly, it is an object of the present invention to provide a plastic case for cartridges of mortar shells which can be easily manufactured of any known suitable plastic material without entailing complicated and expensive manufacturing operations.

Another object of the present invention resides in the provision of a cartridge case for cartridge shells of trench mortars which are made entirely of plastic material yet prevent with certainty the separation of the case from the projectile or shell either during the loading or after tiring.

A further object of the present invention resides in the provision of a cartridge case of the type described above essentially consisting of a plastic material which is securely held in place by frictional engagement.

These and further objects, features, and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawing which shows, for purposes of illustration only, several embodiments in accordance with the present invention and wherein:

FIGURE 1 is a elevational view of a first embodiment of a plastic cartridge case for mortar shells provided with longitudinally extending ribs in accordance with the present invention which extend only over a portion of the length of the case;

FIGURE 2 is a top plan view on the case of FIG- URE l;

FIGURE 3 is an elevational view, similar to FIGURE 1, of a modified embodiment of a plastic cartridge case in accordance with the present invention provided with longitudinal ribs extending over the entire length of the case;

FIGURE 4 is a partial elevational View of a still further moditied embodiment, partly in cross section, of a plastic cartridge case for mortar shells provided with circular ribs in accordance with the present invention;

FIGURE 5 is an elevational view, similar to FIGURES l and 3, of still another modified embodiment of a plastic cartridge case for mortar shells provided with a circular rib in accordance with the present invention, with parts thereof broken away for the sake of clarity;

FIGURE 6 is a partial axial cross sectional view illustrating the cartridge of FIGURE 4 in a cartridge chamber;

FIGURE 7 is a partial axial cross sectional view of the FIGURE 5 cartridge in a cartridge chamber; and

FIGURE 8 is a partial cross sectional view perpendicular to the cartridge axis showing the cartridge according to any one of the FIGURES 1-3 in a cartridge chamber.

Referring now to the drawing wherein like reference numerals are used throughout the various views to designate like parts, reference numeral 1 designates in all figures a plastic cartridge case while reference numeral Z designates a metallic 'bottom piece, all of conventional design.

In the embodiment according to FIGURES 1 and 2, three ribs 3 are formed into the head of the case 1 which extend only over a part of the length of the case 1. The contact circle of the three ribs 3, as measured in a circumferential direction, has a diameter D which is larger than the diameter of the cartridge chamber (not shown) I of a conventional mortar. When pressing the cartridge into the chamber, the ribs 3 abut under slight deformation against the wall of the cartridge chamber andY thus hold securely fast the cartridge, as shown in FIGURE S.

The embodiment according to FIGURE 3 corresponds to that of FIGURE l, however in this embodiment the ribs 5 extend over the entire length of the case 1.

The case 1 according to FIGURE 4 is provided with a number of annularly shaped ribs 6, which, during the pressing-in operation are deformed by an easy folding 3 over when the cartridge is pressed into the cartridge chamber, as shown in FIGURE 6.

In the embodiment according to FIGURE 5, a conically shaped ring 7 open in the direction toward the cartridge bottom 2 is formed into the case 1 which ring 7 is slightly compressed from the dotted line normal unstressed position 7 as shown in FIGURE 7 during the insertion of the cartridge and which prevents by its spreading eect a falling out of the cartridge.

While we have shown and described several embodiments in accordance with the present invention, it is understood that the same is not limited thereto but is susceptible of numerous changes and modifications as known to a person skilled in the art. For example, in all of the embodiments disclosed and illustrated herein, the ribs can also be sub-divided in any suitable manner into individual sections. Furthermore, any suitable plas tic material known in the prior art which possesses the desired characteristics and properties may be used with the present invention, such as polyethylene, polystyrene, polyvinyl chloride, polyamide, acetylcellulose.

Thus, while we have shown and described several embodiments in accordance with the present invention, the same is obviously not limited thereto but may be modied in numerous ways as known to a person skilled in the art, and we therefore do not wish to be limited to the details shown and described herein but intend to cover all such changes and modifications as are encompassed by the scope of the appended claims.

We claim:

1. An integral case of plastic material for cartridges red within the predetermined fixed diameter bore of a cartridge chamber, comprising: a substantially tubular cartridge case, outwardly extending plastic rib means homogeneously integrated on the exterior of said cartridge case; the diameter of the exterior contact circle as measured in the circumferential direction of said rib means being larger than the predetermined xed diameter of the bore of the cartridge chamber within which said case is to be inserted; said rib means being operable to resiliently engage the interior of the bore of the cartridge chamber by deforming inwardly to tightly hold said case within the bore of the cartridge chamber during the firing of the propellant within said case; said rib means including a hollow annular rustum and a tubular lip axially extending from the largest diameter end of said frustum.

2. An integral case of plastic material for cartridges fired within the predetermined fixed diameter bore of a cartridge chamber, comprising: a substantially tubular cartridge case; outwardly extending plastic rib means liomogeneously integrated on the exterior of said cartridge case; the diameter of the exterior contact circle as measured in the circumferential direction of said rib means being larger than the predetermined fixed diameter of the bore of the cartridge chamber within which said case is to be inserted; said rib means `being operable to resiliently engage the interior of the bore of the cartridge chamber by deforming inwardly to tightly hold said case within the bore of the cartridge chamber during the ring of the propellant within said case; said rib means including an annular first portion outwardly and rearwardly extending from said cartridge case and a tubular portion axially rearwardly extending from the outermost end of said irst portion.

3. The device of claim 1l wherein said rib means is only at the rearward end of said cartridge case, and a metallic bottom piece closing the rearward end of said tubular cartridge case.

4. A mortar projectile comprising: a solid mortar projectile portion having a fixed diameter bore forming a cartridge chamber; a substantially tubular cartridge case within said bore; outwardly extending rib means on the exterior of said cartridge case; the diameter of the exterior contact circle, as measured in the circumferential direction before said cartridge case in inserted into said bore, of said rib means being larger than the predetermined fixed diameter of said bore; said rib means being operable to resiliently engage the interior of said bore by deforming inwardly to tightly hold said case within said bore of said cartridge chamber during the firing of the propellant within said case and projection of said projectile; and said rib means including a hollow annular frustum portion and a tubular lip axially extending from the largest diameter end of said frustum portion.

References Cited UNITED STATES PATENTS 185,548 12/1876 Kinney 102-43 1,788,637 1/1931 Schmidt 102-43 1,940,657 12/1933 Woodford 102-43 2,048,267 7/1936 Keith 102-43 3,103,170 9/1963 Covington et al. 102-43 2,178,599 11/1939 McCormick 102-49 FOREIGN PATENTS 783,204 7/1935 France. 352,334 4/1922 Germany. 1,024,067 1/1953 France.

SAMUEL W. ENGLE, Primary Examiner.

BENJAMIN A. BORCHELT, Examiner.

R. F. STAHL, Assistant Examiner. 

1. AN INTEGRAL CASE OF PLASTIC MATERIAL FOR CARTRIDGES FIRED WITHIN THE PREDETERMINED FIXED DIAMETER BORE OF A CARTRIDGE CHAMBER, COMPRISING: A SUBSTANTIALLY TUBULAR CARTRIDGE CASE, OUTWARDLY EXTENDING PLASTIC RIB MEANS HOMOGENEOUSLY INTEGRATED ON THE EXTERIOR OF SAID CARTRIDGE CASE; THE DIAMETER OF THE EXTERIOR CONTACT CIRCLE AS MEASURED IN THE CIRCUMFERENTIAL DIRECTION OF SAID RIB MEANS BEING LARGER THAN THE PREDETERMINED FIXED DIAMETER OF THE BORE OF THE CARTRIDGE CHAMBER WITHIN WHICH SAID 